Twisting of strands to form ply constructions



'May 2l, 1946.

A. P.4 LEWIS TWISTING OF STRANDS TO FORM A FLY CONSTRUC-TI'ON Filed Sept. '7. 1944 INVENTOR ZFLL NN. SQ@ hw uw Patented May 2.1, 1946 UNITED f STATES PATENT oFFlcE TWISTING F STRANDS TO FORM PLY CONSTRUCTIONS Arthur P. Lewis, Fairhaven, Mass., assgnor 4to United States Rubber Company, New York, N. Y., a corporation of New Jersey Application September 7, 1944, Serial No. 552,994

' 5 Claims,

, This invention'relates to mechanism for twisting together a plurality of strands, and more particularly to a method of and 4means for equalizing the tension o f such strands as they apfproach the lpoint where they are twisted together. Y

In the Clarkson Patent No. 2,343,535 for Mechanism for twisting together a plurality ofstrands it is stated that the mechanism disclosed will not twist the strands together symmetrically to produce thedesired ply construction unless the tension upon the different strands is equal or nearly equal, and the patent shows and describes one form of mechanism for automatically equalizing the tension of the strands as .they approach the point at whichl they are twisted together.v

While the mechanism disclosed in this Clarkson patent works very well, the present invention contemplates an improved construction over that of the Clarkson patent for edualizing the tension of the strands, the present construction being more simple than that of the Clarkson patent.

The construction of the present invention could be employed with various types of twisting mechanism for twisting strands together by advancing them in spaced relation to each other parallel to a central axis and at the same time revolving these strands about such axis to twist them -together. The present invention however was developed primarily for use in connection with the type of twisting mechanism forming the .subject matter of the above mentioned Clarkson patent,

and is therefore shown and described as associated with that type of twisting mechanism.

In carrying out the present invention the yarns, cords or strands which are advanced in` spaced relation to each other and to a central axis about which they are revolved to twist them together, are deflected inwardly towards the axis of rotation at a point along their path of travel so as to form a loop in each strand. These loops are floatingly connected so that one pulls against the other as the tension upon the strands tends to straighten out these loops. The result of this is that the amount each strand is deflected from its straight line position will be inversely proportional to its relative tension. That is if one strand is under high tension and the other strand is under a much lower tension, thehigh tension strand will have its loop practically straightened out so that it will pass relatively freely to the point-at which the strands are twisted together, whereas the lower tension strand whichl at this instance will be deflectedto form a. deep loop will travel less freely to lthe point. at which the i is vmounted on a supporting cone I4 that is 'supv strands'are twisted together. The effect of this` The extremely simple construction of the pres- 4 ent invention for automatically equalizing the tension of such strands and method of equalizing their tension will be more fully understood from the following description when read in connection with the accompanying drawing wherein:

Fig. 1 is a schematic side elevation with parts insection of the twisting mechanism shown in the above-mentioned Clarkson patent, but equipped with the tension equalizing means of the present invention.

Fig. 2 on a larger scale is a, longitudinal sectional view through the tension equalizing means shown near the right hand end of the twisting mechanism of Fig. 1; and 1 Fig. 3 is a view similar to Fig. 2 showing a modification of the` invention.

The twisting mechanism shown in Fig. 1 of the drawing is designed to l twist together yarns, threads or strands by forming a balloon in .one strand and by revolving this balloon about the let-off package of another strand to twist the strandstogether 4at a point intermediateA their ends, without similarly rotating the letfoi packages for the strands or the take-up package for the plied constuction. The effect of this'is Ito ply the strandstogether without altering appreciably the manufacturing twist ofthe individual l strands.

In Fig. 1 of the drawing there is shown what is termed the first let-off package I0 and a secwithdrawn endwise from the package, Il without the necessity of rotating these packages as the strands are unwound therefrom. The package I0 ported bythe shaft I5 extending laterally from the frame or upright I6. The strand I2 upon b eing unwound from its package I0 passes through` a'pigtail guide II. disposed on the central axis through the package I but at some distance from the package, and this guide is supported by a bracket I8. v

The strand I2 passes from the pigtail guide 'I'I through an opening I9 at one end`oi a flier arm that is rigidly secured to the hollow twisting spindle 2|, and extending opposite from the arm 20 isthe counterbalancing arm 22. The twisting spindle 2| 'is rotatably supported by the machine frame or bracket 23 and is adapted to be driven by the whorl 24 and belt 25. The 'strand I2 after passing through the opening I9 travels along the arm 2 0 to the hollow spindle 2| and then through the hole 26 into this hollow shaft and lengthwise therein in a righthand direction.

The second let-olf package II is shown as mounted upon a cone 2'I which is supported by the hollow shaft za, and uns shaft is non-rotatv ably supportedby the rotating spindle 2| through the ball bearlngs29 consisting of the inner rings rigidly secured to a projecting end ofthe revolv- 5 ing spindle 2| and theouter rings tightly'tted within the casing 38 secured to the shaft 28.

'I'his ball bearing construction permits the hollow twisting spindle 2| to be rotated without rotating the spindle 28 which it supports, and in order to prevent the smal1 amount of friction which may be imparted from the rotating spindle 2| to the spindle 28 from turning the latter,

, a weight such as 3| may be rigidly secured to the casing 30 to hang downwardly therefrom in a vertical direction and has at its outer end the projection 32 positioned to clear the full package I I.

In the construction shown the package Il is supported so that its smaller end faces the smallerv end of the rst package I IJ,- and the construc-v tion ispreferably such that the strand which is unwound from the package II may be `pulled endwise therefrom and then advanced axially i through thispackage within the hollow supportv ing shaft'28.

To accomplish this and at the same time prevent the unwinding strand from dragging unduly upon the -smaller end of the conical package a fairly long tubular guide 33 is propreferably mounted for slidable longitudinal4 adjustment thereupon so as to vary the distance between the end walls 35 and 33 as will be ap.-

parent from Figs. 2 and i3'. After the housing 3'I has been adjusted upon the spindle 2| to the desired position it may be locked in this position by tightening the set screw 40.

The means shown in Figs. 1 and 2 of the draw- I ing for automatically equalizing the tension of the strands I2 and I3 operate as follows.

spindle 2|, and the strand |2is threaded through the aligned guide openings 36 and 39 at one side of the spindle axis, whereas the strand I3 is threaded vthrough the valigned guide openings 36 and 39 at the other side of the spindle axis. This may be done by using a wire with a hook onthe end of it for drawing these strands I2 and I3 through the openings just mentioned. This will cause the strands I2 and I3 to lie in spaced'parallel relation to each other within the casing24.'

This casing is then preferably rotated through .about 360 with respect to -the hollow spindle 2| so 'as to twist -each strand about theother as shown in full lines in Fig. 2. The set screw 40 is then tightened to lock the part in the position in which they are shown in Fig.'2. It will be seen from this view, that each strand is now looped about the otherv strand within the receptacle 31, and the arrangement is such that one strand slides withinthe loopof the other as they advance toward the point where they are twisted together.

The p`oint'4ll at which the loop of one strand engages thelop, 0f ythe other strand will be a floating point and will lie upon the central axis upon which' the spindle 2| rotates only whenV the tension upon the two strands is substantially the If the strand I2 should be subjected tol same. a tension considerably higher than that of the strand I3 the point 4| )where the strand loops I vi'nterengagewill be shifted to some such p oint as 4| where the highly tensioned strandv I2 assumes nearly a straight line position while it forms a deep loop in the strand I3 which is under less tension. The effect of this will be to cause the nearly straight strand I2 to pass more freely through the housing -3'I than the deeply looped strand I3, with the result that the tension of these two strands will be about.equal as they l pass-through the guide openings 39 to .the point where they are twisted together.

The tension equalizing device of the present invention has therefore been shown as mounted upon the right hand end of the rotating hollow spindle 2|, but it will be'understood' that the present tension device may be used upon other types of strand twisting devices than that shown in Fig. 1 of the drawing.

The hollow spindle 2| as will be apparent from Figs. 1, 2 and 3 ofthe drawing has provided at its discharge end a guide disc 35 in which is provided the strand guiding holes 3B disposed upon the opposite sides of and some distance from the central axis of the spindle 2| as shown.

To the right hand end of this hollow spindle 2| issecured the cup-like housing 3I having the closed end 38 in which are formed the spaced guide holes 39 adapted to be aligned with the holes 36. This housing as shown ts snugly over the 'outer end portions of the spindle 2| and ils On the other hand if thestrand I3.shou1d be subjected to a greater tension than the strand I2 the point at Y which the loops are interengaged will be shifted to some such position as 4|. I While the construction shown in Fig. 2 ofl the drawing is extremely 'simple the sliding of the looped portion of one strand through the 'looped portion of the other strand'may tendvv to chafe both strands. 'I'his diillculty -may be Iovercome by employing the modified construction shown 'in Fig.'3 of the drawing in which a small guide ring 42 formed' of metal or plastic material is employed through which the strands I2 and. I3 will slide as shown. This ring 42 is floatlngly sup- -ported bythe looped portions of the strands I2 and4 I3 and -will shift rfrom the central axis of rotation' towards the straight line posltionvofone strand or the other as the relative tension of the two strands varies, it being apparent, that the strand lwhich isV nearlyj straight will pass more freely through the ring 42 than the strand which is displaced to form a, d eep loop. This will tend The strands I2 and I3 are drawn through the hollow Y automatically to equalize the tension of the strands as they passthrough the guide holes 33.

izing device of the present invention will exert upon the two strands I 2 and I3 may be increased somewhat by adjusting the housing 31 from the full line position to the dotted line position vin which it is shown in Figs. 2 and 3.. This will cause the strands to form sharper. loops So as to increase thetension which one exerts upon the other as they pass through the `housing 31.

'I'he strands I2 and I3 when plied together pass through the chuck 44 supported by the bracket 45. and these strands are pulled forward from their respective packages I and II andl through the spindle 2| and housing 31 by the rolls 48 and", one of which is positively driven. 'I'he plied yarn is wound one or more times around these spaced rolls to prevent it from slipping.

It will be seen-from the foregoing that the present invention .provides an extremely simple construction for automatically equalizing the tension of strands as they approach the point where they are twisted together as described to revolving spindle having means for guiding twisted together, comprisin'g a member for de ilecting each strand inwardly towards said axis so that each strand is held-in a looped condition by the tension of the other strand andthe depth of each loop will be inversely proportional to the relative tension oi' the two strands.

3. Twisting mechanism for twisting strands together to form a ply construction, comprising a revolving spindle having means `for guiding the strands lengthwise thereof in spaced relation to the axis upon which the spindle rotates to thereby twist the strands together upon said axis; Y

and means for equalizing-the tension of said strands as they approach the point where .they are twisted together, comprising a guide fordefiecting the strands inwardly towards said axis and through which guide the strands pass so as, to form a loop in each strand,said guide lbeing of strands to form a ply construction and of coni' trolling the tension of the strands being twisted,

which comprises advancing strands in spaced relation to each other and to a central axis and rotating them about said axis vto twist them to-A gether; and equalizing the tension of said strands strands lengthwise thereof in spaced relation to the spindles' axis to thereby twist the strands ,so as to form a loop in each strand whereby the guide is iioatingly supported solely by such loops for movement towards the straight path of travel 2.' Twisting mechanism for twisting two strands together to form a ply' construction, comprisinga revolving spindle having means for 4guiding the strands lengthwise thereof at opposite sides of of. the strandl that is under the greatest tension.

theaxis upon .which the spindle rotates to therel 'by twist the together upon said axis: and

meansiorequaliaingthetensionotsaidstrands as they approach the point where they are as they approach the poitswher they are twisted togetherby deflecting a portion-of each strand inwardly toward said axis to form sliding loops that are i'loatingly connected so that one pulls against-the other and the depth of each loop willbe inversely proportional to its vrelation to each otheri and to a central axis and rotating them about said axis to twist them together; and equalizing the tension of said strands as they approach the point where they are twisted together by deflecting a portion of each. strand inwardly toward lsaid axis to form sliding loops that are floatingly connected so that one pulls against the other and the amount each is defloated from'its straight line vrposition will be invlsely proportional to the tension of each strand Aa'rnoanxawrs..

respectively. 

